1. Field of the Invention
The present invention relates to a main printer which has a first tank and a first head, a sub printer which has a second tank having a volume smaller than that of the first tank and a second head, a printer system which is composed of the main printer and the sub printer, and an ink supply method for supplying the ink from the first tank and the second tank.
2. Description of the Related Art
A portable type printer has been suggested, which is small in size as compared with a stationary type printer provided with a paper feed/discharge mechanism and which can be carried about, for example, with one hand (see, for example, Japanese Patent Application Laid-open No. 2002-361934). The portable type printer has a small casing. Therefore, the portable type printer cannot carry any large volume ink tank as the ink tank for storing the discharge ink to be discharged to a recording member or medium. In view of the above, in order to supplement with the ink when the residual amount is in shortage while carrying an ink tank having a small volume, an exclusive station is prepared, to which the portable type printer is subjected to the docking. In the case of an exclusive station disclosed in Japanese Patent Application Laid-open No. 2002-361934, when the portable type printer is subjected to the docking, the ink tank of the portable type printer is supplemented with the ink from the exclusive station.
However, the exclusive station as described above finds no way of use except when the portable printer is supplemented with the ink. Further, the installation space is not small as well. In this viewpoint, it is not affirmed that the exclusive station as described above is convenient for the user. On the other hand, if the ink tank of the portable type printer itself is exchangeable, then the volume of the ink tank is small, and hence it is necessary that the exchange operation should be performed frequently, which is not preferred.